tools/vm/page-types.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * page-types: Tool for querying page flags
   4  *
   5  * Copyright (C) 2009 Intel corporation
   6  *
   7  * Authors: Wu Fengguang <fengguang.wu@intel.com>
   8  */
   9
  10 #define _FILE_OFFSET_BITS 64
  11 #define _GNU_SOURCE
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <unistd.h>
  15 #include <stdint.h>
  16 #include <stdarg.h>
  17 #include <string.h>
  18 #include <getopt.h>
  19 #include <limits.h>
  20 #include <assert.h>
  21 #include <ftw.h>
  22 #include <time.h>
  23 #include <setjmp.h>
  24 #include <signal.h>
  25 #include <sys/types.h>
  26 #include <sys/errno.h>
  27 #include <sys/fcntl.h>
  28 #include <sys/mount.h>
  29 #include <sys/statfs.h>
  30 #include <sys/mman.h>
  31 #include "../../include/uapi/linux/magic.h"
  32 #include "../../include/uapi/linux/kernel-page-flags.h"
  33 #include <api/fs/fs.h>
  34
  35 #ifndef MAX_PATH
  36 # define MAX_PATH 256
  37 #endif
  38
  39 #ifndef STR
  40 # define _STR(x) #x
  41 # define STR(x) _STR(x)
  42 #endif
  43
  44 /*
  45  * pagemap kernel ABI bits
  46  */
  47
  48 #define PM_ENTRY_BYTES          8
  49 #define PM_PFRAME_BITS          55
  50 #define PM_PFRAME_MASK          ((1LL << PM_PFRAME_BITS) - 1)
  51 #define PM_PFRAME(x)            ((x) & PM_PFRAME_MASK)
  52 #define MAX_SWAPFILES_SHIFT     5
  53 #define PM_SWAP_OFFSET(x)       (((x) & PM_PFRAME_MASK) >> MAX_SWAPFILES_SHIFT)
  54 #define PM_SOFT_DIRTY           (1ULL << 55)
  55 #define PM_MMAP_EXCLUSIVE       (1ULL << 56)
  56 #define PM_FILE                 (1ULL << 61)
  57 #define PM_SWAP                 (1ULL << 62)
  58 #define PM_PRESENT              (1ULL << 63)
  59
  60 /*
  61  * kernel page flags
  62  */
  63
  64 #define KPF_BYTES               8
  65 #define PROC_KPAGEFLAGS         "/proc/kpageflags"
  66 #define PROC_KPAGECOUNT         "/proc/kpagecount"
  67 #define PROC_KPAGECGROUP        "/proc/kpagecgroup"
  68
  69 #define SYS_KERNEL_MM_PAGE_IDLE "/sys/kernel/mm/page_idle/bitmap"
  70
  71 /* [32-] kernel hacking assistances */
  72 #define KPF_RESERVED            32
  73 #define KPF_MLOCKED             33
  74 #define KPF_MAPPEDTODISK        34
  75 #define KPF_PRIVATE             35
  76 #define KPF_PRIVATE_2           36
  77 #define KPF_OWNER_PRIVATE       37
  78 #define KPF_ARCH                38
  79 #define KPF_UNCACHED            39
  80 #define KPF_SOFTDIRTY           40
  81
  82 /* [48-] take some arbitrary free slots for expanding overloaded flags
  83  * not part of kernel API
  84  */
  85 #define KPF_READAHEAD           48
  86 #define KPF_SLOB_FREE           49
  87 #define KPF_SLUB_FROZEN         50
  88 #define KPF_SLUB_DEBUG          51
  89 #define KPF_FILE                61
  90 #define KPF_SWAP                62
  91 #define KPF_MMAP_EXCLUSIVE      63
  92
  93 #define KPF_ALL_BITS            ((uint64_t)~0ULL)
  94 #define KPF_HACKERS_BITS        (0xffffULL << 32)
  95 #define KPF_OVERLOADED_BITS     (0xffffULL << 48)
  96 #define BIT(name)               (1ULL << KPF_##name)
  97 #define BITS_COMPOUND           (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
  98
  99 static const char * const page_flag_names[] = {
 100         [KPF_LOCKED]            = "L:locked",
 101         [KPF_ERROR]             = "E:error",
 102         [KPF_REFERENCED]        = "R:referenced",
 103         [KPF_UPTODATE]          = "U:uptodate",
 104         [KPF_DIRTY]             = "D:dirty",
 105         [KPF_LRU]               = "l:lru",
 106         [KPF_ACTIVE]            = "A:active",
 107         [KPF_SLAB]              = "S:slab",
 108         [KPF_WRITEBACK]         = "W:writeback",
 109         [KPF_RECLAIM]           = "I:reclaim",
 110         [KPF_BUDDY]             = "B:buddy",
 111
 112         [KPF_MMAP]              = "M:mmap",
 113         [KPF_ANON]              = "a:anonymous",
 114         [KPF_SWAPCACHE]         = "s:swapcache",
 115         [KPF_SWAPBACKED]        = "b:swapbacked",
 116         [KPF_COMPOUND_HEAD]     = "H:compound_head",
 117         [KPF_COMPOUND_TAIL]     = "T:compound_tail",
 118         [KPF_HUGE]              = "G:huge",
 119         [KPF_UNEVICTABLE]       = "u:unevictable",
 120         [KPF_HWPOISON]          = "X:hwpoison",
 121         [KPF_NOPAGE]            = "n:nopage",
 122         [KPF_KSM]               = "x:ksm",
 123         [KPF_THP]               = "t:thp",
 124         [KPF_OFFLINE]           = "o:offline",
 125         [KPF_PGTABLE]           = "g:pgtable",
 126         [KPF_ZERO_PAGE]         = "z:zero_page",
 127         [KPF_IDLE]              = "i:idle_page",
 128
 129         [KPF_RESERVED]          = "r:reserved",
 130         [KPF_MLOCKED]           = "m:mlocked",
 131         [KPF_MAPPEDTODISK]      = "d:mappedtodisk",
 132         [KPF_PRIVATE]           = "P:private",
 133         [KPF_PRIVATE_2]         = "p:private_2",
 134         [KPF_OWNER_PRIVATE]     = "O:owner_private",
 135         [KPF_ARCH]              = "h:arch",
 136         [KPF_UNCACHED]          = "c:uncached",
 137         [KPF_SOFTDIRTY]         = "f:softdirty",
 138
 139         [KPF_READAHEAD]         = "I:readahead",
 140         [KPF_SLOB_FREE]         = "P:slob_free",
 141         [KPF_SLUB_FROZEN]       = "A:slub_frozen",
 142         [KPF_SLUB_DEBUG]        = "E:slub_debug",
 143
 144         [KPF_FILE]              = "F:file",
 145         [KPF_SWAP]              = "w:swap",
 146         [KPF_MMAP_EXCLUSIVE]    = "1:mmap_exclusive",
 147 };
 148
 149
 150 /*
 151  * data structures
 152  */
 153
 154 static int              opt_raw;        /* for kernel developers */
 155 static int              opt_list;       /* list pages (in ranges) */
 156 static int              opt_mark_idle;  /* set accessed bit */
 157 static int              opt_no_summary; /* don't show summary */
 158 static pid_t            opt_pid;        /* process to walk */
 159 const char              *opt_file;      /* file or directory path */
 160 static uint64_t         opt_cgroup;     /* cgroup inode */
 161 static int              opt_list_cgroup;/* list page cgroup */
 162 static int              opt_list_mapcnt;/* list page map count */
 163 static const char       *opt_kpageflags;/* kpageflags file to parse */
 164
 165 #define MAX_ADDR_RANGES 1024
 166 static int              nr_addr_ranges;
 167 static unsigned long    opt_offset[MAX_ADDR_RANGES];
 168 static unsigned long    opt_size[MAX_ADDR_RANGES];
 169
 170 #define MAX_VMAS        10240
 171 static int              nr_vmas;
 172 static unsigned long    pg_start[MAX_VMAS];
 173 static unsigned long    pg_end[MAX_VMAS];
 174
 175 #define MAX_BIT_FILTERS 64
 176 static int              nr_bit_filters;
 177 static uint64_t         opt_mask[MAX_BIT_FILTERS];
 178 static uint64_t         opt_bits[MAX_BIT_FILTERS];
 179
 180 static int              page_size;
 181
 182 static int              pagemap_fd;
 183 static int              kpageflags_fd;
 184 static int              kpagecount_fd = -1;
 185 static int              kpagecgroup_fd = -1;
 186 static int              page_idle_fd = -1;
 187
 188 static int              opt_hwpoison;
 189 static int              opt_unpoison;
 190
 191 static const char       *hwpoison_debug_fs;
 192 static int              hwpoison_inject_fd;
 193 static int              hwpoison_forget_fd;
 194
 195 #define HASH_SHIFT      13
 196 #define HASH_SIZE       (1 << HASH_SHIFT)
 197 #define HASH_MASK       (HASH_SIZE - 1)
 198 #define HASH_KEY(flags) (flags & HASH_MASK)
 199
 200 static unsigned long    total_pages;
 201 static unsigned long    nr_pages[HASH_SIZE];
 202 static uint64_t         page_flags[HASH_SIZE];
 203
 204
 205 /*
 206  * helper functions
 207  */
 208
 209 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 210
 211 #define min_t(type, x, y) ({                    \
 212         type __min1 = (x);                      \
 213         type __min2 = (y);                      \
 214         __min1 < __min2 ? __min1 : __min2; })
 215
 216 #define max_t(type, x, y) ({                    \
 217         type __max1 = (x);                      \
 218         type __max2 = (y);                      \
 219         __max1 > __max2 ? __max1 : __max2; })
 220
 221 static unsigned long pages2mb(unsigned long pages)
 222 {
 223         return (pages * page_size) >> 20;
 224 }
 225
 226 static void fatal(const char *x, ...)
 227 {
 228         va_list ap;
 229
 230         va_start(ap, x);
 231         vfprintf(stderr, x, ap);
 232         va_end(ap);
 233         exit(EXIT_FAILURE);
 234 }
 235
 236 static int checked_open(const char *pathname, int flags)
 237 {
 238         int fd = open(pathname, flags);
 239
 240         if (fd < 0) {
 241                 perror(pathname);
 242                 exit(EXIT_FAILURE);
 243         }
 244
 245         return fd;
 246 }
 247
 248 /*
 249  * pagemap/kpageflags routines
 250  */
 251
 252 static unsigned long do_u64_read(int fd, const char *name,
 253                                  uint64_t *buf,
 254                                  unsigned long index,
 255                                  unsigned long count)
 256 {
 257         long bytes;
 258
 259         if (index > ULONG_MAX / 8)
 260                 fatal("index overflow: %lu\n", index);
 261
 262         bytes = pread(fd, buf, count * 8, (off_t)index * 8);
 263         if (bytes < 0) {
 264                 perror(name);
 265                 exit(EXIT_FAILURE);
 266         }
 267         if (bytes % 8)
 268                 fatal("partial read: %lu bytes\n", bytes);
 269
 270         return bytes / 8;
 271 }
 272
 273 static unsigned long kpageflags_read(uint64_t *buf,
 274                                      unsigned long index,
 275                                      unsigned long pages)
 276 {
 277         return do_u64_read(kpageflags_fd, opt_kpageflags, buf, index, pages);
 278 }
 279
 280 static unsigned long kpagecgroup_read(uint64_t *buf,
 281                                       unsigned long index,
 282                                       unsigned long pages)
 283 {
 284         if (kpagecgroup_fd < 0)
 285                 return pages;
 286
 287         return do_u64_read(kpagecgroup_fd, opt_kpageflags, buf, index, pages);
 288 }
 289
 290 static unsigned long kpagecount_read(uint64_t *buf,
 291                                      unsigned long index,
 292                                      unsigned long pages)
 293 {
 294         return kpagecount_fd < 0 ? pages :
 295                 do_u64_read(kpagecount_fd, PROC_KPAGECOUNT,
 296                             buf, index, pages);
 297 }
 298
 299 static unsigned long pagemap_read(uint64_t *buf,
 300                                   unsigned long index,
 301                                   unsigned long pages)
 302 {
 303         return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
 304 }
 305
 306 static unsigned long pagemap_pfn(uint64_t val)
 307 {
 308         unsigned long pfn;
 309
 310         if (val & PM_PRESENT)
 311                 pfn = PM_PFRAME(val);
 312         else
 313                 pfn = 0;
 314
 315         return pfn;
 316 }
 317
 318 static unsigned long pagemap_swap_offset(uint64_t val)
 319 {
 320         return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0;
 321 }
 322
 323 /*
 324  * page flag names
 325  */
 326
 327 static char *page_flag_name(uint64_t flags)
 328 {
 329         static char buf[65];
 330         int present;
 331         size_t i, j;
 332
 333         for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 334                 present = (flags >> i) & 1;
 335                 if (!page_flag_names[i]) {
 336                         if (present)
 337                                 fatal("unknown flag bit %d\n", i);
 338                         continue;
 339                 }
 340                 buf[j++] = present ? page_flag_names[i][0] : '_';
 341         }
 342
 343         return buf;
 344 }
 345
 346 static char *page_flag_longname(uint64_t flags)
 347 {
 348         static char buf[1024];
 349         size_t i, n;
 350
 351         for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 352                 if (!page_flag_names[i])
 353                         continue;
 354                 if ((flags >> i) & 1)
 355                         n += snprintf(buf + n, sizeof(buf) - n, "%s,",
 356                                         page_flag_names[i] + 2);
 357         }
 358         if (n)
 359                 n--;
 360         buf[n] = '\0';
 361
 362         return buf;
 363 }
 364
 365
 366 /*
 367  * page list and summary
 368  */
 369
 370 static void show_page_range(unsigned long voffset, unsigned long offset,
 371                             unsigned long size, uint64_t flags,
 372                             uint64_t cgroup, uint64_t mapcnt)
 373 {
 374         static uint64_t      flags0;
 375         static uint64_t      cgroup0;
 376         static uint64_t      mapcnt0;
 377         static unsigned long voff;
 378         static unsigned long index;
 379         static unsigned long count;
 380
 381         if (flags == flags0 && cgroup == cgroup0 && mapcnt == mapcnt0 &&
 382             offset == index + count && size && voffset == voff + count) {
 383                 count += size;
 384                 return;
 385         }
 386
 387         if (count) {
 388                 if (opt_pid)
 389                         printf("%lx\t", voff);
 390                 if (opt_file)
 391                         printf("%lu\t", voff);
 392                 if (opt_list_cgroup)
 393                         printf("@%llu\t", (unsigned long long)cgroup0);
 394                 if (opt_list_mapcnt)
 395                         printf("%lu\t", mapcnt0);
 396                 printf("%lx\t%lx\t%s\n",
 397                                 index, count, page_flag_name(flags0));
 398         }
 399
 400         flags0 = flags;
 401         cgroup0 = cgroup;
 402         mapcnt0 = mapcnt;
 403         index  = offset;
 404         voff   = voffset;
 405         count  = size;
 406 }
 407
 408 static void flush_page_range(void)
 409 {
 410         show_page_range(0, 0, 0, 0, 0, 0);
 411 }
 412
 413 static void show_page(unsigned long voffset, unsigned long offset,
 414                       uint64_t flags, uint64_t cgroup, uint64_t mapcnt)
 415 {
 416         if (opt_pid)
 417                 printf("%lx\t", voffset);
 418         if (opt_file)
 419                 printf("%lu\t", voffset);
 420         if (opt_list_cgroup)
 421                 printf("@%llu\t", (unsigned long long)cgroup);
 422         if (opt_list_mapcnt)
 423                 printf("%lu\t", mapcnt);
 424
 425         printf("%lx\t%s\n", offset, page_flag_name(flags));
 426 }
 427
 428 static void show_summary(void)
 429 {
 430         size_t i;
 431
 432         printf("             flags\tpage-count       MB"
 433                 "  symbolic-flags\t\t\tlong-symbolic-flags\n");
 434
 435         for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
 436                 if (nr_pages[i])
 437                         printf("0x%016llx\t%10lu %8lu  %s\t%s\n",
 438                                 (unsigned long long)page_flags[i],
 439                                 nr_pages[i],
 440                                 pages2mb(nr_pages[i]),
 441                                 page_flag_name(page_flags[i]),
 442                                 page_flag_longname(page_flags[i]));
 443         }
 444
 445         printf("             total\t%10lu %8lu\n",
 446                         total_pages, pages2mb(total_pages));
 447 }
 448
 449
 450 /*
 451  * page flag filters
 452  */
 453
 454 static int bit_mask_ok(uint64_t flags)
 455 {
 456         int i;
 457
 458         for (i = 0; i < nr_bit_filters; i++) {
 459                 if (opt_bits[i] == KPF_ALL_BITS) {
 460                         if ((flags & opt_mask[i]) == 0)
 461                                 return 0;
 462                 } else {
 463                         if ((flags & opt_mask[i]) != opt_bits[i])
 464                                 return 0;
 465                 }
 466         }
 467
 468         return 1;
 469 }
 470
 471 static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
 472 {
 473         /* SLOB/SLUB overload several page flags */
 474         if (flags & BIT(SLAB)) {
 475                 if (flags & BIT(PRIVATE))
 476                         flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
 477                 if (flags & BIT(ACTIVE))
 478                         flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
 479                 if (flags & BIT(ERROR))
 480                         flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
 481         }
 482
 483         /* PG_reclaim is overloaded as PG_readahead in the read path */
 484         if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
 485                 flags ^= BIT(RECLAIM) | BIT(READAHEAD);
 486
 487         if (pme & PM_SOFT_DIRTY)
 488                 flags |= BIT(SOFTDIRTY);
 489         if (pme & PM_FILE)
 490                 flags |= BIT(FILE);
 491         if (pme & PM_SWAP)
 492                 flags |= BIT(SWAP);
 493         if (pme & PM_MMAP_EXCLUSIVE)
 494                 flags |= BIT(MMAP_EXCLUSIVE);
 495
 496         return flags;
 497 }
 498
 499 static uint64_t well_known_flags(uint64_t flags)
 500 {
 501         /* hide flags intended only for kernel hacker */
 502         flags &= ~KPF_HACKERS_BITS;
 503
 504         /* hide non-hugeTLB compound pages */
 505         if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
 506                 flags &= ~BITS_COMPOUND;
 507
 508         return flags;
 509 }
 510
 511 static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme)
 512 {
 513         if (opt_raw)
 514                 flags = expand_overloaded_flags(flags, pme);
 515         else
 516                 flags = well_known_flags(flags);
 517
 518         return flags;
 519 }
 520
 521 /*
 522  * page actions
 523  */
 524
 525 static void prepare_hwpoison_fd(void)
 526 {
 527         char buf[MAX_PATH + 1];
 528
 529         hwpoison_debug_fs = debugfs__mount();
 530         if (!hwpoison_debug_fs) {
 531                 perror("mount debugfs");
 532                 exit(EXIT_FAILURE);
 533         }
 534
 535         if (opt_hwpoison && !hwpoison_inject_fd) {
 536                 snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
 537                         hwpoison_debug_fs);
 538                 hwpoison_inject_fd = checked_open(buf, O_WRONLY);
 539         }
 540
 541         if (opt_unpoison && !hwpoison_forget_fd) {
 542                 snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
 543                         hwpoison_debug_fs);
 544                 hwpoison_forget_fd = checked_open(buf, O_WRONLY);
 545         }
 546 }
 547
 548 static int hwpoison_page(unsigned long offset)
 549 {
 550         char buf[100];
 551         int len;
 552
 553         len = sprintf(buf, "0x%lx\n", offset);
 554         len = write(hwpoison_inject_fd, buf, len);
 555         if (len < 0) {
 556                 perror("hwpoison inject");
 557                 return len;
 558         }
 559         return 0;
 560 }
 561
 562 static int unpoison_page(unsigned long offset)
 563 {
 564         char buf[100];
 565         int len;
 566
 567         len = sprintf(buf, "0x%lx\n", offset);
 568         len = write(hwpoison_forget_fd, buf, len);
 569         if (len < 0) {
 570                 perror("hwpoison forget");
 571                 return len;
 572         }
 573         return 0;
 574 }
 575
 576 static int mark_page_idle(unsigned long offset)
 577 {
 578         static unsigned long off;
 579         static uint64_t buf;
 580         int len;
 581
 582         if ((offset / 64 == off / 64) || buf == 0) {
 583                 buf |= 1UL << (offset % 64);
 584                 off = offset;
 585                 return 0;
 586         }
 587
 588         len = pwrite(page_idle_fd, &buf, 8, 8 * (off / 64));
 589         if (len < 0) {
 590                 perror("mark page idle");
 591                 return len;
 592         }
 593
 594         buf = 1UL << (offset % 64);
 595         off = offset;
 596
 597         return 0;
 598 }
 599
 600 /*
 601  * page frame walker
 602  */
 603
 604 static size_t hash_slot(uint64_t flags)
 605 {
 606         size_t k = HASH_KEY(flags);
 607         size_t i;
 608
 609         /* Explicitly reserve slot 0 for flags 0: the following logic
 610          * cannot distinguish an unoccupied slot from slot (flags==0).
 611          */
 612         if (flags == 0)
 613                 return 0;
 614
 615         /* search through the remaining (HASH_SIZE-1) slots */
 616         for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
 617                 if (!k || k >= ARRAY_SIZE(page_flags))
 618                         k = 1;
 619                 if (page_flags[k] == 0) {
 620                         page_flags[k] = flags;
 621                         return k;
 622                 }
 623                 if (page_flags[k] == flags)
 624                         return k;
 625         }
 626
 627         fatal("hash table full: bump up HASH_SHIFT?\n");
 628         exit(EXIT_FAILURE);
 629 }
 630
 631 static void add_page(unsigned long voffset, unsigned long offset,
 632                      uint64_t flags, uint64_t cgroup, uint64_t mapcnt,
 633                      uint64_t pme)
 634 {
 635         flags = kpageflags_flags(flags, pme);
 636
 637         if (!bit_mask_ok(flags))
 638                 return;
 639
 640         if (opt_cgroup && cgroup != (uint64_t)opt_cgroup)
 641                 return;
 642
 643         if (opt_hwpoison)
 644                 hwpoison_page(offset);
 645         if (opt_unpoison)
 646                 unpoison_page(offset);
 647
 648         if (opt_mark_idle)
 649                 mark_page_idle(offset);
 650
 651         if (opt_list == 1)
 652                 show_page_range(voffset, offset, 1, flags, cgroup, mapcnt);
 653         else if (opt_list == 2)
 654                 show_page(voffset, offset, flags, cgroup, mapcnt);
 655
 656         nr_pages[hash_slot(flags)]++;
 657         total_pages++;
 658 }
 659
 660 #define KPAGEFLAGS_BATCH        (64 << 10)      /* 64k pages */
 661 static void walk_pfn(unsigned long voffset,
 662                      unsigned long index,
 663                      unsigned long count,
 664                      uint64_t pme)
 665 {
 666         uint64_t buf[KPAGEFLAGS_BATCH];
 667         uint64_t cgi[KPAGEFLAGS_BATCH];
 668         uint64_t cnt[KPAGEFLAGS_BATCH];
 669         unsigned long batch;
 670         unsigned long pages;
 671         unsigned long i;
 672
 673         /*
 674          * kpagecgroup_read() reads only if kpagecgroup were opened, but
 675          * /proc/kpagecgroup might even not exist, so it's better to fill
 676          * them with zeros here.
 677          */
 678         if (count == 1)
 679                 cgi[0] = 0;
 680         else
 681                 memset(cgi, 0, sizeof cgi);
 682
 683         while (count) {
 684                 batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
 685                 pages = kpageflags_read(buf, index, batch);
 686                 if (pages == 0)
 687                         break;
 688
 689                 if (kpagecgroup_read(cgi, index, pages) != pages)
 690                         fatal("kpagecgroup returned fewer pages than expected");
 691
 692                 if (kpagecount_read(cnt, index, pages) != pages)
 693                         fatal("kpagecount returned fewer pages than expected");
 694
 695                 for (i = 0; i < pages; i++)
 696                         add_page(voffset + i, index + i,
 697                                  buf[i], cgi[i], cnt[i], pme);
 698
 699                 index += pages;
 700                 count -= pages;
 701         }
 702 }
 703
 704 static void walk_swap(unsigned long voffset, uint64_t pme)
 705 {
 706         uint64_t flags = kpageflags_flags(0, pme);
 707
 708         if (!bit_mask_ok(flags))
 709                 return;
 710
 711         if (opt_cgroup)
 712                 return;
 713
 714         if (opt_list == 1)
 715                 show_page_range(voffset, pagemap_swap_offset(pme),
 716                                 1, flags, 0, 0);
 717         else if (opt_list == 2)
 718                 show_page(voffset, pagemap_swap_offset(pme), flags, 0, 0);
 719
 720         nr_pages[hash_slot(flags)]++;
 721         total_pages++;
 722 }
 723
 724 #define PAGEMAP_BATCH   (64 << 10)
 725 static void walk_vma(unsigned long index, unsigned long count)
 726 {
 727         uint64_t buf[PAGEMAP_BATCH];
 728         unsigned long batch;
 729         unsigned long pages;
 730         unsigned long pfn;
 731         unsigned long i;
 732
 733         while (count) {
 734                 batch = min_t(unsigned long, count, PAGEMAP_BATCH);
 735                 pages = pagemap_read(buf, index, batch);
 736                 if (pages == 0)
 737                         break;
 738
 739                 for (i = 0; i < pages; i++) {
 740                         pfn = pagemap_pfn(buf[i]);
 741                         if (pfn)
 742                                 walk_pfn(index + i, pfn, 1, buf[i]);
 743                         if (buf[i] & PM_SWAP)
 744                                 walk_swap(index + i, buf[i]);
 745                 }
 746
 747                 index += pages;
 748                 count -= pages;
 749         }
 750 }
 751
 752 static void walk_task(unsigned long index, unsigned long count)
 753 {
 754         const unsigned long end = index + count;
 755         unsigned long start;
 756         int i = 0;
 757
 758         while (index < end) {
 759
 760                 while (pg_end[i] <= index)
 761                         if (++i >= nr_vmas)
 762                                 return;
 763                 if (pg_start[i] >= end)
 764                         return;
 765
 766                 start = max_t(unsigned long, pg_start[i], index);
 767                 index = min_t(unsigned long, pg_end[i], end);
 768
 769                 assert(start < index);
 770                 walk_vma(start, index - start);
 771         }
 772 }
 773
 774 static void add_addr_range(unsigned long offset, unsigned long size)
 775 {
 776         if (nr_addr_ranges >= MAX_ADDR_RANGES)
 777                 fatal("too many addr ranges\n");
 778
 779         opt_offset[nr_addr_ranges] = offset;
 780         opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
 781         nr_addr_ranges++;
 782 }
 783
 784 static void walk_addr_ranges(void)
 785 {
 786         int i;
 787
 788         kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
 789
 790         if (!nr_addr_ranges)
 791                 add_addr_range(0, ULONG_MAX);
 792
 793         for (i = 0; i < nr_addr_ranges; i++)
 794                 if (!opt_pid)
 795                         walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0);
 796                 else
 797                         walk_task(opt_offset[i], opt_size[i]);
 798
 799         if (opt_mark_idle)
 800                 mark_page_idle(0);
 801
 802         close(kpageflags_fd);
 803 }
 804
 805
 806 /*
 807  * user interface
 808  */
 809
 810 static const char *page_flag_type(uint64_t flag)
 811 {
 812         if (flag & KPF_HACKERS_BITS)
 813                 return "(r)";
 814         if (flag & KPF_OVERLOADED_BITS)
 815                 return "(o)";
 816         return "   ";
 817 }
 818
 819 static void usage(void)
 820 {
 821         size_t i, j;
 822
 823         printf(
 824 "page-types [options]\n"
 825 "            -r|--raw                   Raw mode, for kernel developers\n"
 826 "            -d|--describe flags        Describe flags\n"
 827 "            -a|--addr    addr-spec     Walk a range of pages\n"
 828 "            -b|--bits    bits-spec     Walk pages with specified bits\n"
 829 "            -c|--cgroup  path|@inode   Walk pages within memory cgroup\n"
 830 "            -p|--pid     pid           Walk process address space\n"
 831 "            -f|--file    filename      Walk file address space\n"
 832 "            -i|--mark-idle             Mark pages idle\n"
 833 "            -l|--list                  Show page details in ranges\n"
 834 "            -L|--list-each             Show page details one by one\n"
 835 "            -C|--list-cgroup           Show cgroup inode for pages\n"
 836 "            -M|--list-mapcnt           Show page map count\n"
 837 "            -N|--no-summary            Don't show summary info\n"
 838 "            -X|--hwpoison              hwpoison pages\n"
 839 "            -x|--unpoison              unpoison pages\n"
 840 "            -F|--kpageflags filename   kpageflags file to parse\n"
 841 "            -h|--help                  Show this usage message\n"
 842 "flags:\n"
 843 "            0x10                       bitfield format, e.g.\n"
 844 "            anon                       bit-name, e.g.\n"
 845 "            0x10,anon                  comma-separated list, e.g.\n"
 846 "addr-spec:\n"
 847 "            N                          one page at offset N (unit: pages)\n"
 848 "            N+M                        pages range from N to N+M-1\n"
 849 "            N,M                        pages range from N to M-1\n"
 850 "            N,                         pages range from N to end\n"
 851 "            ,M                         pages range from 0 to M-1\n"
 852 "bits-spec:\n"
 853 "            bit1,bit2                  (flags & (bit1|bit2)) != 0\n"
 854 "            bit1,bit2=bit1             (flags & (bit1|bit2)) == bit1\n"
 855 "            bit1,~bit2                 (flags & (bit1|bit2)) == bit1\n"
 856 "            =bit1,bit2                 flags == (bit1|bit2)\n"
 857 "bit-names:\n"
 858         );
 859
 860         for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 861                 if (!page_flag_names[i])
 862                         continue;
 863                 printf("%16s%s", page_flag_names[i] + 2,
 864                                  page_flag_type(1ULL << i));
 865                 if (++j > 3) {
 866                         j = 0;
 867                         putchar('\n');
 868                 }
 869         }
 870         printf("\n                                   "
 871                 "(r) raw mode bits  (o) overloaded bits\n");
 872 }
 873
 874 static unsigned long long parse_number(const char *str)
 875 {
 876         unsigned long long n;
 877
 878         n = strtoll(str, NULL, 0);
 879
 880         if (n == 0 && str[0] != '0')
 881                 fatal("invalid name or number: %s\n", str);
 882
 883         return n;
 884 }
 885
 886 static void parse_pid(const char *str)
 887 {
 888         FILE *file;
 889         char buf[5000];
 890
 891         opt_pid = parse_number(str);
 892
 893         sprintf(buf, "/proc/%d/pagemap", opt_pid);
 894         pagemap_fd = checked_open(buf, O_RDONLY);
 895
 896         sprintf(buf, "/proc/%d/maps", opt_pid);
 897         file = fopen(buf, "r");
 898         if (!file) {
 899                 perror(buf);
 900                 exit(EXIT_FAILURE);
 901         }
 902
 903         while (fgets(buf, sizeof(buf), file) != NULL) {
 904                 unsigned long vm_start;
 905                 unsigned long vm_end;
 906                 unsigned long long pgoff;
 907                 int major, minor;
 908                 char r, w, x, s;
 909                 unsigned long ino;
 910                 int n;
 911
 912                 n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
 913                            &vm_start,
 914                            &vm_end,
 915                            &r, &w, &x, &s,
 916                            &pgoff,
 917                            &major, &minor,
 918                            &ino);
 919                 if (n < 10) {
 920                         fprintf(stderr, "unexpected line: %s\n", buf);
 921                         continue;
 922                 }
 923                 pg_start[nr_vmas] = vm_start / page_size;
 924                 pg_end[nr_vmas] = vm_end / page_size;
 925                 if (++nr_vmas >= MAX_VMAS) {
 926                         fprintf(stderr, "too many VMAs\n");
 927                         break;
 928                 }
 929         }
 930         fclose(file);
 931 }
 932
 933 static void show_file(const char *name, const struct stat *st)
 934 {
 935         unsigned long long size = st->st_size;
 936         char atime[64], mtime[64];
 937         long now = time(NULL);
 938
 939         printf("%s\tInode: %u\tSize: %llu (%llu pages)\n",
 940                         name, (unsigned)st->st_ino,
 941                         size, (size + page_size - 1) / page_size);
 942
 943         strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime));
 944         strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime));
 945
 946         printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n",
 947                         mtime, now - st->st_mtime,
 948                         atime, now - st->st_atime);
 949 }
 950
 951 static sigjmp_buf sigbus_jmp;
 952
 953 static void * volatile sigbus_addr;
 954
 955 static void sigbus_handler(int sig, siginfo_t *info, void *ucontex)
 956 {
 957         (void)sig;
 958         (void)ucontex;
 959         sigbus_addr = info ? info->si_addr : NULL;
 960         siglongjmp(sigbus_jmp, 1);
 961 }
 962
 963 static struct sigaction sigbus_action = {
 964         .sa_sigaction = sigbus_handler,
 965         .sa_flags = SA_SIGINFO,
 966 };
 967
 968 static void walk_file(const char *name, const struct stat *st)
 969 {
 970         uint8_t vec[PAGEMAP_BATCH];
 971         uint64_t buf[PAGEMAP_BATCH], flags;
 972         uint64_t cgroup = 0;
 973         uint64_t mapcnt = 0;
 974         unsigned long nr_pages, pfn, i;
 975         off_t off, end = st->st_size;
 976         int fd;
 977         ssize_t len;
 978         void *ptr;
 979         int first = 1;
 980
 981         fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW);
 982
 983         for (off = 0; off < end; off += len) {
 984                 nr_pages = (end - off + page_size - 1) / page_size;
 985                 if (nr_pages > PAGEMAP_BATCH)
 986                         nr_pages = PAGEMAP_BATCH;
 987                 len = nr_pages * page_size;
 988
 989                 ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off);
 990                 if (ptr == MAP_FAILED)
 991                         fatal("mmap failed: %s", name);
 992
 993                 /* determine cached pages */
 994                 if (mincore(ptr, len, vec))
 995                         fatal("mincore failed: %s", name);
 996
 997                 /* turn off readahead */
 998                 if (madvise(ptr, len, MADV_RANDOM))
 999                         fatal("madvice failed: %s", name);
1000
1001                 if (sigsetjmp(sigbus_jmp, 1)) {
1002                         end = off + sigbus_addr ? sigbus_addr - ptr : 0;
1003                         fprintf(stderr, "got sigbus at offset %lld: %s\n",
1004                                         (long long)end, name);
1005                         goto got_sigbus;
1006                 }
1007
1008                 /* populate ptes */
1009                 for (i = 0; i < nr_pages ; i++) {
1010                         if (vec[i] & 1)
1011                                 (void)*(volatile int *)(ptr + i * page_size);
1012                 }
1013 got_sigbus:
1014
1015                 /* turn off harvesting reference bits */
1016                 if (madvise(ptr, len, MADV_SEQUENTIAL))
1017                         fatal("madvice failed: %s", name);
1018
1019                 if (pagemap_read(buf, (unsigned long)ptr / page_size,
1020                                         nr_pages) != nr_pages)
1021                         fatal("cannot read pagemap");
1022
1023                 munmap(ptr, len);
1024
1025                 for (i = 0; i < nr_pages; i++) {
1026                         pfn = pagemap_pfn(buf[i]);
1027                         if (!pfn)
1028                                 continue;
1029                         if (!kpageflags_read(&flags, pfn, 1))
1030                                 continue;
1031                         if (!kpagecgroup_read(&cgroup, pfn, 1))
1032                                 fatal("kpagecgroup_read failed");
1033                         if (!kpagecount_read(&mapcnt, pfn, 1))
1034                                 fatal("kpagecount_read failed");
1035                         if (first && opt_list) {
1036                                 first = 0;
1037                                 flush_page_range();
1038                                 show_file(name, st);
1039                         }
1040                         add_page(off / page_size + i, pfn,
1041                                  flags, cgroup, mapcnt, buf[i]);
1042                 }
1043         }
1044
1045         close(fd);
1046 }
1047
1048 int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f)
1049 {
1050         (void)f;
1051         switch (type) {
1052         case FTW_F:
1053                 if (S_ISREG(st->st_mode))
1054                         walk_file(name, st);
1055                 break;
1056         case FTW_DNR:
1057                 fprintf(stderr, "cannot read dir: %s\n", name);
1058                 break;
1059         }
1060         return 0;
1061 }
1062
1063 static void walk_page_cache(void)
1064 {
1065         struct stat st;
1066
1067         kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
1068         pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY);
1069         sigaction(SIGBUS, &sigbus_action, NULL);
1070
1071         if (stat(opt_file, &st))
1072                 fatal("stat failed: %s\n", opt_file);
1073
1074         if (S_ISREG(st.st_mode)) {
1075                 walk_file(opt_file, &st);
1076         } else if (S_ISDIR(st.st_mode)) {
1077                 /* do not follow symlinks and mountpoints */
1078                 if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0)
1079                         fatal("nftw failed: %s\n", opt_file);
1080         } else
1081                 fatal("unhandled file type: %s\n", opt_file);
1082
1083         close(kpageflags_fd);
1084         close(pagemap_fd);
1085         signal(SIGBUS, SIG_DFL);
1086 }
1087
1088 static void parse_file(const char *name)
1089 {
1090         opt_file = name;
1091 }
1092
1093 static void parse_cgroup(const char *path)
1094 {
1095         if (path[0] == '@') {
1096                 opt_cgroup = parse_number(path + 1);
1097                 return;
1098         }
1099
1100         struct stat st;
1101
1102         if (stat(path, &st))
1103                 fatal("stat failed: %s: %m\n", path);
1104
1105         if (!S_ISDIR(st.st_mode))
1106                 fatal("cgroup supposed to be a directory: %s\n", path);
1107
1108         opt_cgroup = st.st_ino;
1109 }
1110
1111 static void parse_addr_range(const char *optarg)
1112 {
1113         unsigned long offset;
1114         unsigned long size;
1115         char *p;
1116
1117         p = strchr(optarg, ',');
1118         if (!p)
1119                 p = strchr(optarg, '+');
1120
1121         if (p == optarg) {
1122                 offset = 0;
1123                 size   = parse_number(p + 1);
1124         } else if (p) {
1125                 offset = parse_number(optarg);
1126                 if (p[1] == '\0')
1127                         size = ULONG_MAX;
1128                 else {
1129                         size = parse_number(p + 1);
1130                         if (*p == ',') {
1131                                 if (size < offset)
1132                                         fatal("invalid range: %lu,%lu\n",
1133                                                         offset, size);
1134                                 size -= offset;
1135                         }
1136                 }
1137         } else {
1138                 offset = parse_number(optarg);
1139                 size   = 1;
1140         }
1141
1142         add_addr_range(offset, size);
1143 }
1144
1145 static void add_bits_filter(uint64_t mask, uint64_t bits)
1146 {
1147         if (nr_bit_filters >= MAX_BIT_FILTERS)
1148                 fatal("too much bit filters\n");
1149
1150         opt_mask[nr_bit_filters] = mask;
1151         opt_bits[nr_bit_filters] = bits;
1152         nr_bit_filters++;
1153 }
1154
1155 static uint64_t parse_flag_name(const char *str, int len)
1156 {
1157         size_t i;
1158
1159         if (!*str || !len)
1160                 return 0;
1161
1162         if (len <= 8 && !strncmp(str, "compound", len))
1163                 return BITS_COMPOUND;
1164
1165         for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
1166                 if (!page_flag_names[i])
1167                         continue;
1168                 if (!strncmp(str, page_flag_names[i] + 2, len))
1169                         return 1ULL << i;
1170         }
1171
1172         return parse_number(str);
1173 }
1174
1175 static uint64_t parse_flag_names(const char *str, int all)
1176 {
1177         const char *p    = str;
1178         uint64_t   flags = 0;
1179
1180         while (1) {
1181                 if (*p == ',' || *p == '=' || *p == '\0') {
1182                         if ((*str != '~') || (*str == '~' && all && *++str))
1183                                 flags |= parse_flag_name(str, p - str);
1184                         if (*p != ',')
1185                                 break;
1186                         str = p + 1;
1187                 }
1188                 p++;
1189         }
1190
1191         return flags;
1192 }
1193
1194 static void parse_bits_mask(const char *optarg)
1195 {
1196         uint64_t mask;
1197         uint64_t bits;
1198         const char *p;
1199
1200         p = strchr(optarg, '=');
1201         if (p == optarg) {
1202                 mask = KPF_ALL_BITS;
1203                 bits = parse_flag_names(p + 1, 0);
1204         } else if (p) {
1205                 mask = parse_flag_names(optarg, 0);
1206                 bits = parse_flag_names(p + 1, 0);
1207         } else if (strchr(optarg, '~')) {
1208                 mask = parse_flag_names(optarg, 1);
1209                 bits = parse_flag_names(optarg, 0);
1210         } else {
1211                 mask = parse_flag_names(optarg, 0);
1212                 bits = KPF_ALL_BITS;
1213         }
1214
1215         add_bits_filter(mask, bits);
1216 }
1217
1218 static void parse_kpageflags(const char *name)
1219 {
1220         opt_kpageflags = name;
1221 }
1222
1223 static void describe_flags(const char *optarg)
1224 {
1225         uint64_t flags = parse_flag_names(optarg, 0);
1226
1227         printf("0x%016llx\t%s\t%s\n",
1228                 (unsigned long long)flags,
1229                 page_flag_name(flags),
1230                 page_flag_longname(flags));
1231 }
1232
1233 static const struct option opts[] = {
1234         { "raw"       , 0, NULL, 'r' },
1235         { "pid"       , 1, NULL, 'p' },
1236         { "file"      , 1, NULL, 'f' },
1237         { "addr"      , 1, NULL, 'a' },
1238         { "bits"      , 1, NULL, 'b' },
1239         { "cgroup"    , 1, NULL, 'c' },
1240         { "describe"  , 1, NULL, 'd' },
1241         { "mark-idle" , 0, NULL, 'i' },
1242         { "list"      , 0, NULL, 'l' },
1243         { "list-each" , 0, NULL, 'L' },
1244         { "list-cgroup", 0, NULL, 'C' },
1245         { "list-mapcnt", 0, NULL, 'M' },
1246         { "no-summary", 0, NULL, 'N' },
1247         { "hwpoison"  , 0, NULL, 'X' },
1248         { "unpoison"  , 0, NULL, 'x' },
1249         { "kpageflags", 0, NULL, 'F' },
1250         { "help"      , 0, NULL, 'h' },
1251         { NULL        , 0, NULL, 0 }
1252 };
1253
1254 int main(int argc, char *argv[])
1255 {
1256         int c;
1257
1258         page_size = getpagesize();
1259
1260         while ((c = getopt_long(argc, argv,
1261                                 "rp:f:a:b:d:c:CilLMNXxF:h",
1262                                 opts, NULL)) != -1) {
1263                 switch (c) {
1264                 case 'r':
1265                         opt_raw = 1;
1266                         break;
1267                 case 'p':
1268                         parse_pid(optarg);
1269                         break;
1270                 case 'f':
1271                         parse_file(optarg);
1272                         break;
1273                 case 'a':
1274                         parse_addr_range(optarg);
1275                         break;
1276                 case 'b':
1277                         parse_bits_mask(optarg);
1278                         break;
1279                 case 'c':
1280                         parse_cgroup(optarg);
1281                         break;
1282                 case 'C':
1283                         opt_list_cgroup = 1;
1284                         break;
1285                 case 'd':
1286                         describe_flags(optarg);
1287                         exit(0);
1288                 case 'i':
1289                         opt_mark_idle = 1;
1290                         break;
1291                 case 'l':
1292                         opt_list = 1;
1293                         break;
1294                 case 'L':
1295                         opt_list = 2;
1296                         break;
1297                 case 'M':
1298                         opt_list_mapcnt = 1;
1299                         break;
1300                 case 'N':
1301                         opt_no_summary = 1;
1302                         break;
1303                 case 'X':
1304                         opt_hwpoison = 1;
1305                         prepare_hwpoison_fd();
1306                         break;
1307                 case 'x':
1308                         opt_unpoison = 1;
1309                         prepare_hwpoison_fd();
1310                         break;
1311                 case 'F':
1312                         parse_kpageflags(optarg);
1313                         break;
1314                 case 'h':
1315                         usage();
1316                         exit(0);
1317                 default:
1318                         usage();
1319                         exit(1);
1320                 }
1321         }
1322
1323         if (!opt_kpageflags)
1324                 opt_kpageflags = PROC_KPAGEFLAGS;
1325
1326         if (opt_cgroup || opt_list_cgroup)
1327                 kpagecgroup_fd = checked_open(PROC_KPAGECGROUP, O_RDONLY);
1328
1329         if (opt_list && opt_list_mapcnt)
1330                 kpagecount_fd = checked_open(PROC_KPAGECOUNT, O_RDONLY);
1331
1332         if (opt_mark_idle && opt_file)
1333                 page_idle_fd = checked_open(SYS_KERNEL_MM_PAGE_IDLE, O_RDWR);
1334
1335         if (opt_list && opt_pid)
1336                 printf("voffset\t");
1337         if (opt_list && opt_file)
1338                 printf("foffset\t");
1339         if (opt_list && opt_list_cgroup)
1340                 printf("cgroup\t");
1341         if (opt_list && opt_list_mapcnt)
1342                 printf("map-cnt\t");
1343
1344         if (opt_list == 1)
1345                 printf("offset\tlen\tflags\n");
1346         if (opt_list == 2)
1347                 printf("offset\tflags\n");
1348
1349         if (opt_file)
1350                 walk_page_cache();
1351         else
1352                 walk_addr_ranges();
1353
1354         if (opt_list == 1)
1355                 flush_page_range();
1356
1357         if (opt_no_summary)
1358                 return 0;
1359
1360         if (opt_list)
1361                 printf("\n\n");
1362
1363         show_summary();
1364
1365         if (opt_list_mapcnt)
1366                 close(kpagecount_fd);
1367
1368         if (page_idle_fd >= 0)
1369                 close(page_idle_fd);
1370
1371         return 0;
1372 }